Are nonsingular black holes with super-Planckian hair ruled out by S2 star data?

M. Cadoni;M. De Laurentis;I. De Martino;R. Della Monica;M. Oi;A. P. Sanna

2023-01-01

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Abstract

We investigate a nonsingular black hole spacetime representing a strong deformation of the Schwarzs-child solution with mass M by an additional hair if, which may be hierarchically larger than the Planck scale. The spacetime is an exact solution of Einstein's equations sourced by an anisotropic fluid. The model presents a de Sitter core and O(if2/r2) slow-decaying corrections to the Schwarzschild solution. These solutions are thermodynamically preferred when 0.2 less than or similar to if/GM less than or similar to 0.3 and are characterized by strong deviations in the orbits of test particles from the Schwarzschild case. In particular, we find corrections to the perihelion precession angle scaling linearly with if. We test our model using the available data for the orbits of the S2 star around SgrA*. These data strongly constrain the value of the hair if, casting an upper bound on it of similar to 0.47GM but do not rule out the possible existence of regular black holes with super-Planckian hair.